Rotary piston type internal combustion engine

A rotary piston type internal combustion engine comprising:

• a housing including a rotor housing and side housings;
• a cylindrical rotor holding bore formed in the housing;
• a rotor as a rotary piston held in the rotor holding bore rotatably around a rotation center which is an axial center of the rotor holding bore, the rotor including at a portion of an outer circumferential surface a minimum radius surface smaller in diameter than a bore surface which is a circumferential surface of the rotor holding bore, and including a protecting portion for partitioning whose top portion is in contact with the bore surface with gas seal engagement, said rotor including, on said outer circumferential surface, the minimum radius face, a first inclined curved pressurization surface extending with an increasing radius from a trailing side end of the minimum radius surface to the top of the projecting portion, and a second inclined curved pressure reception surface extending with an increasing radius from a leading side end of the minimum radius surface to the top of the projecting portion, the radius of said second inclined surface increasing at a greater rate than the radius of said first inclined surface;
• an axial member coaxial with the rotor holding bore, the axial member supporting the rotor on the housing, and being rotative in unison with the rotor;
• an intake port and an exhaust port which are formed in the housing, the exhaust port being disposed near the intake port on the trailing side in the direction of rotor rotation;
• a first partitioning means for partitioning hermetically between the outer circumferential surface of the rotor and the bore surface while engaging the outer circumferential surface, on an opposite side to the intake Port and exhaust port with respect to the axial center of the rotor holding bore, the first partitioning means including:
• a first swinging partition member comprising an axial portion positioned so as to approximately circumscribe the bore surface and supported on the housing so as to swing around an axial center parallel with the axial center of the rotor holding bore, and a swinging partition plate formed integrally with the axial portion and extended by a given length from the axial portion in the direction of rotor rotation and having an engaging curved surface for engaging hermetically with the rotor;
• a first holding cavity formed in the rotor housing and being open to the bore surface, and being capable of holding the swinging partition plate of the first swinging partition member;
• and
• a first biasing means for forcing the first swinging partition member so that the swinging partition plate may be forced against the rotor;
• a second partitioning means for partitioning hermetically between the outer circumferential surface of the rotor and the bore surface while engaging the outer circumferential face, between the intake port and exhaust port;
• and
• three chambers formed by partitioning with the first partitioning means, the second partitioning means and the projecting portion, between the outer circumferential surface of the rotor and the bore surface within the rotor holding bore, the three chambers varying their capacities according to rotor rotation, said three chambers including,
• when the projecting portion of the rotor is positioned between the intake port and the first partitioning means in the direction of rotation, a suction chamber communicating with the intake port, a compression chamber between the projecting portion and the first partitioning means, and an exhaust chamber communicating with the exhaust port;
• and
• when the projecting portion of the rotor is positioned between the first partitioning means and the exhaust port in the direction of rotation, a suction
• chamber or a compression chamber, an expansion chamber, and an exhaust chamber;
• the rotor housing being provided with a combustion subchamber opening to at least a portion of an interior end face of the first holding cavity, the combustion subchamber being capable of being switched as a closed condition closed hermetically by the swinging partition plate of the first swinging partition member and as an opened condition opened to the first holding cavity and the expansion chamber;
• a gas inlet passage formed in the first swinging partition member for introducing compressed fuel-air mixture or compressed air in the compression chamber into the combustion subchamber;
• and
• an opening/closing valve means having a valve shaft fitted in through an axial bore in the axial portion of the first swinging partition member, the opening/closing valve means opening and closing the gas inlet passage at timings depending on rotation phase of the rotor.

A rotary engine, comprising:

• a housing defining a rotor holding bore;
• a rotor disposed in said rotor holding bore and being rotatable in a rotational direction;
• a swinging partition member swingably disposed adjacent to said rotor holding bore, said swinging partition member engaging an outer circumferential surface of said rotor, said swinging partition member being swingable into a holding cavity communicating with said rotor holding bore;
• a portion of said rotor holding bore located upstream of said swinging partition member relative to said rotational direction being an intake/compression chamber;
• a portion of said rotor holding bore located downstream of said swinging partition member relative to said rotational direction being an expansion/exhaust chamber;
• said housing defining a combustion subchamber adjacent to said holding cavity,
• said combustion subchamber being communicable with said intake/compression chamber when said swinging partition member is located in a first angular range of rotation,
• said combustion subchamber being communicable with said expansion/exhaust chamber when said swinging partition member is located in a second angular range of rotation.

A swinging partition arrangement in a rotary engine including a housing defining each of a rotor holding bore and a combustion subchamber, and a rotor disposed in said rotor holding bore and being rotatable in a rotational direction, said swinging partition arrangement comprising:

• a swinging partition member swingably disposed adjacent to said rotor holding bore, said swinging partition member being swingable into a holding cavity communicating with said rotor holding bore,
• said swinging partition member engaging an outer circumferential surface of said rotor to divide an intake/compression chamber of said rotor holding bore located upstream of said swinging partition member relative to said rotational direction from an expansion/exhaust chamber of said rotor holding bore located downstream of said swinging partition member relative to said rotational direction,
• said swinging partition member being swingable in a first angular range of rotation to communicate said combustion subchamber with said intake/compression chamber,
• said swinging partition member being swingable in a second angular range of rotation to communicate said combustion subchamber with said expansion/exhaust chamber.